package com.yxjx.duoxue.customview;

import android.content.Context;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.widget.ScrollView;

public class InnerScrollView extends ScrollView {

    /**
     */
    public OutScrollView parentScrollView;

    public InnerScrollView(Context context, AttributeSet attrs) {
        super(context, attrs);

    }

    private int lastScrollDelta = 0;

    public void resume() {
//        overScrollBy(0, -lastScrollDelta, 0, getScrollY(), 0, getScrollRange(), 0, 0, true);
        scrollBy(0, -lastScrollDelta);
        lastScrollDelta = 0;
    }

    int mTop = 0;

    /**
     * 将targetView滚到最顶端
     */
    public void scrollTo(View targetView) {

        int oldScrollY = getScrollY();
        int top = targetView.getTop() - mTop;
        int delatY = top - oldScrollY;
        lastScrollDelta = delatY;
//        overScrollBy(0, delatY, 0, getScrollY(), 0, getScrollRange(), 0, 0, true);
        scrollBy(0, delatY);
    }

    private int getScrollRange() {
        int scrollRange = 0;
        if (getChildCount() > 0) {
            View child = getChildAt(0);
            scrollRange = Math.max(0, child.getHeight() - (getHeight()));
        }
        return scrollRange;
    }

    int currentY;

    @Override
    public boolean onInterceptTouchEvent(MotionEvent ev) {
        if (parentScrollView == null) {
            return super.onInterceptTouchEvent(ev);
        } else {
        	// tab非置顶时inner scroll不获取scroll事件。
            if (ev.getAction() == MotionEvent.ACTION_DOWN) {
				if (parentScrollView.isTabTop()) {
					// 将父scrollview的滚动事件拦截
					currentY = (int) ev.getY();
					setParentScrollAble(false);
				}
                return super.onInterceptTouchEvent(ev);
            } else if (ev.getAction() == MotionEvent.ACTION_UP) {
                // 把滚动事件恢复给父Scrollview
                setParentScrollAble(true);
            } else if (ev.getAction() == MotionEvent.ACTION_MOVE) {
            	
            }
        }
        return super.onInterceptTouchEvent(ev);
    }

    @Override
    public boolean onTouchEvent(MotionEvent ev) {
        View child = getChildAt(0);
        if (parentScrollView != null) {
            if (ev.getAction() == MotionEvent.ACTION_MOVE) {
                int height = child.getMeasuredHeight();
                height = height - getMeasuredHeight();

                // System.out.println("height=" + height);
                int scrollY = getScrollY();
                // System.out.println("scrollY" + scrollY);
                int y = (int)ev.getY();
                
                
				// 手指向下滑动
				if (currentY < y) {
					if (scrollY <= 0) {
						// 如果向下滑动到头，就把滚动交给父Scrollview
						setParentScrollAble(true);
						return false;
					} else {
						setParentScrollAble(false);
					}
				} else if (currentY > y) {
					if (scrollY >= height) {
						// 如果向上滑动到头，就把滚动交给父Scrollview
						setParentScrollAble(true);
						return false;
					} else {
						setParentScrollAble(false);

					}

				}
				currentY = y;

                
            }
        }

        return super.onTouchEvent(ev);
    }

    /**
     * 是否把滚动事件交给父scrollview
     * 
     * @param flag
     */
    private void setParentScrollAble(boolean flag) {

        parentScrollView.requestDisallowInterceptTouchEvent(!flag);
    }

    
}
